By any measure, it was one of the worst offseason days in 49ers franchise history. It was your standard harmonic convergence of roster meltdown, free agent horror and one more player being arrested for domestic violence.

Oh, for those gentle times when Santa Clara was simply the home of outdoor ice hockey games. The Levi’s Stadium neighborhood was so much more serene then.

Yet in almost all respects, team owner Jed York and general manager Trent Baalke can only blame themselves for the mess. They teed it all up with their clumsy handling of former coach Jim Harbaugh’s departure (although he wasn’t entirely blameless). Then they exacerbated it with their professions of “winning with class” while in too many cases ignoring their own slogan.

Should we round up the more recent ugly play-by-play?

The weekend kicked off with a report that universally respected 31-year-old running back Frank Gore is leaving for Philadelphia — or now possibly Indianapolis — rather than re-sign with the 49ers.

Then, as Monday dawned, came surprising news that linebacker Patrick Willis will retire at age 30, surprisingly. He is expected to soon be joined by 35-year-old defensive lineman Justin Smith — although Smith told the Sacramento Bee he isn’t yet “100% sure” of his decision and won’t announce it until next week.

Gore and Willis and Smith have been selected to a combined 17 Pro Bowls. That’s a lot of Pro Bowls walking out the door to the parking lot.

Also Monday, 49ers’ offensive guard Mike Iupati (a three-time Pro Bowler) was reported on his way to the Arizona Cardinals as a free agent. Wide receiver Michael Crabtree also seemed likely to sign elsewhere when the free agency period officially opens Tuesday.

Then, toward sundown, we learned that the Santa Clara police arrested 49ers fullback Bruce Miller last week for spousal battery, in spite of the NFL’s ongoing campaign against domestic abuse.

But wait, there’s more! A story by a Houston reporter claimed that the 49ers were shopping quarterback Colin Kaepernick for a possible trade (Baalke quickly and firmly denied it). And there were murmurs that the team might cut linebacker NaVorro Bowman, who spent all last season recuperating from the severe knee injury he sustained in January of 2014. Supposedly, there are concerns that he may fail to pass his 2015 preseason physical, so the 49ers might release him.

Taken individually, each of these developments would be depressing news. But together, they sent 49ers fans into something approaching a nervous breakdown. So let’s do our best to put this in perspective.

Every NFL roster changes, every offseason. Some offseasons are more dramatic than others. In the 49ers’ case, this week probably most compares to 1991, when both Ronnie Lott and Roger Craig were allowed to leave the team in what was then called “Plan B Free Agency.” Both were beloved. Lott became a Hall of Famer. Craig should be there. At the time of their departure, the teeth-gnashing was immense.

However, the franchise survived. The 49ers won the Super Bowl three seasons later. But it took a lot of smart decisions and smart money to get there.

Likewise, the franchise will survive this week. One day, it may even rejoin the NFL’s top tier. The question remains whether York and Baalke can make the smart decisions to get there. They have not done much to build faith in doing so. They need to get out front of their customers as soon as possible, to explain what’s happening.

Remember, the team was 8-8 last season. And that .500 record wasn’t entirely because of the turmoil surrounding Harbaugh’s status, though it played some factor. It’s clear the roster needed some improvement and turnover. But like this?

That said, there is no way to totally judge the Baalke rebuild until after the free agency period and the college draft. Baalke is apparently ready to sign free agent wide receiver Torrey Smith from Baltimore. That’s a start. But what are we to make of another free agent receiver signing — of Jerome Simpson, who has repeatedly violated the NFL’s substance abuse policy at his previous stops? Are the 49ers that needy? Someone needs to explain.

Willis’ choice to retire is the biggest blow. It comes as a stunner because he’s still relatively young. But Willis missed the end of last season with “turf toe,” slang for ripped or torn ligaments in the big toe area. It’s incredibly painful. He had surgery for the problem. But perhaps there were complications. Or perhaps Willis, a thoughtful man, has studied the latest pro football concussion data and wants to exit the meat grinder while he’s still ahead of the game. Either way, the 49ers will have a hard time replacing what Willis meant to the team on the field and off the field, where he was a team leader.

You could say the same for Gore and Smith. New coach Jim Tomsula was definitely not helped by Monday’s events. He is not as dynamic a personality as former coach Jim Harbaugh. Nor does Tomsula have the credibility as a former NFL player himself. He’ll need as much veteran support in the locker room as possible. Willis, Smith and Gore could have been key elements in providing that support.

The overriding thought Monday was that the 49ers’ current window to championships closed firmly. With a hard slam. Baalke has three months before training camp opens to make personnel moves that will disprove that notion. Otherwise, in terms of the NFC West standings . . . look out below.